ProSe UE-to-network relay has been the subject of agreement for example at the 3GPP RAN2#89bis meeting.
In RAN2 contribution (R2-152581), relay selection and reselection were discussed. It mentioned that good PC5 link and Uu link are important for a remote UE to work under the relay UE. It also concluded that PC5 link measurement performed by remote UE and Uu link measurement assistance provided by relay UE together with higher layer criteria can be utilized by remote UE to perform relay reselection. However, while goals might have been discussed no solutions were provided.
In contrast, our subject matter, disclosed herein below, teaches solutions not envisioned by these references.
This section is intended to provide a background or context to the invention disclosed below. The description herein may include concepts that could be pursued, but are not necessarily ones that have been previously conceived, implemented, or described. Therefore, unless otherwise explicitly indicated herein, what is described in this section is not prior art to the description in this application and is not admitted to be prior art by inclusion in this section.
The following abbreviations that may be found in the specification and/or the drawing figures are defined as follows:
3GPP: third generation partnership project;
D2D: Device to Device;
eNB or eNodeB: base station, evolved Node B;
L3: Layer 3
LTE: long term evolution;
LTE-A: long term evolution—advanced;
MME: Mobility Management Entity;
PC5: UE-to-UE direct interface
ProSe: Proximity Services;
QoS: Quality of Service;
RRC: Radio Resource Control
SIB: System Information Block
SGW: Serving Gateway;
SoC: Software on a chip;
DL: downlink
UE: user equipment;
UL: uplink
Uu: radio interface between the UE and the eNB;
v1, v2, etc.: Version 1, version 2, etc.